1. Field of the Invention
The present invention is in the field of storm chokes for closing oil well production lines or pipelines in the event of a break or sudden increase in fluid pressure.
In production lines from oil wells or in pipelines conducting materials from one location to another, a break in the conduit obviously results in loss of considerable fluid and in many instances it is difficult or impossible to cut off flow and serious damage and loss result. A particularly dangerous situation exists in offshore oil production facilities wherein high seas or other marine events often rupture a production line, thus causing spillage of oil in the surrounding waters and such spillage not only contaminates the water but presents an extremely serious fire hazard. In the event of such an occurrence, it has been heretofore extremely difficult to stem flow from the well.
2. General Background
The present invention provides an improved, extremely simple automatic valve that can be placed in a production line or pipeline. The strom choke valve of the present invention comprises an upper and lower valve housing; an upper seat mated into the top of the upper valve housing and a lower seat mated at the connection between the upper and lower valve housings, thereby connecting the lower and upper valve housings; upper and lower valve members mounted onto a longitudinally extending axle having a longitudinal axis substantially coincidental with the longitudinal axis of the upper and lower valve housings and mounted for reciprocal movement therein, the upper and lower valve members thereby being movable for seating engagement with the upper and lower valve seats, respectively; the upper valve member is fixedly mounted to the axle relative to inclined vanes that cause the valve member and the entire axle and the lower valve member to rotate during fluid flow in the production line or pipeline.
Sufficient background has now been afforded to discuss the improvements of the present invention over the prior art, particularly U.S. Pat. No. 3,714,957. The improvements are as follows:
1. The inclined vanes which are mounted to the upper valve member are not subject to closure by fluid flow through the production line, as in U.S. Pat. No. 3,714,957, but rather, the vanes can only be adjusted to variable open positions and can only be closed by means of a vane adjustment nut circumferentially mounted on the axle, below the vanes, the axle being calibrated so that the operator can preset the degree of opening of the vanes in order to allow a specified amount of fluid flow past the vanes, and if this fluid flow is exceeded, the vanes cause the upper and lower valve members and the entire axle to rotate, and exert a lifting force on the upper valve member, and if the fluid flow is increased enough, the vane rotates more rapidly and a greater lifting force is applied to the upper valve member, thereby causing the entire axle and the upper and lower valve members mounted thereto to rise within the upper and lower valve housings, so that the upper and lower valve members are pulled into seating engagement with the upper and lower valve seats, respectively, and thus, automatically close the pipe against further or continued flow therethrough;
2. A lower seal housing having a lower shaft rotatably mounted therein, the lower shaft being mated on its top to the lower end of the lower valve member, the top of the seal housing communicating with the bottom surface of the lower valve member, thereby defining the lowermost movement of the lower valve member; a compression spring circumferentially mounted to the lower portion of the lower shaft at the bottom of the seal housing, and the lower shaft is secured within the seal housing by a lower bushing and an upper bushing, O-ring seals, and a lock ring and washer;
3. A plug having breather vents in its lower portion is mated at its top end with the lower end of the seal housing, thereby fluidly sealing the seal housing; the seal housing is secured within the lower valve housing by means of spiders or support fins being welded to the outer surface of the seal housing and the inner surface of the lower valve housing;
4. The weight of the upper and lower valve members downwardly biases the compression spring mounted to the lower shaft within the seal housing, and this bias can only be reversed by increased fluid flow velocity which causes the inclined vanes mounted to the upper valve member to rotate, thereby exerting a lifting force on the upper valve member and thus, the vanes, the axle, and the lower valve member, and this lifting action is further enhanced by the decompression of the compression spring and the resultant upward movement of the lower shaft and the lower valve member mounted thereto, and thus, the upper axle and the upper valve member, ultimately resulting in the seating engagement of the upper valve member and the lower valve member with the upper and lower valve seats, respectively, thus automatically closing the pipe or production line against further or continued flow therethrough.
The invention disclosed herein contemplates forms for employment in vertical production lines or in horizontal production lines.
Many other objects and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings.